Reamer



I OcL'G, 1936.

J. c. WRIGHT REAMER Filed May 19, 1935 55a 6. h r-lghf Afforneg PatentedOct. 6, 1936 ATENT OFFI REAMER Jesse C. Wright, Los Angeles, Calif.,assignor to Globe Oil Tools Company, Los Nietos, Califi, a corporationof California Application May 19, 1933, Serial No. 671,875 7 Claims.(01. 255-73) This invention relates to a well drilling tool and relatesmore particularly to a well reamer. It is a general object of thisinvention to provide a simple, practical and effective well reamerhaving 1 novel and eiilcient replaceable cutters.

Another object of the invention is to provide a reamer for use in therotary method of well drilling including rotatable cutters havingparticularly effective cutting parts.

Another object of the invention is to provide cutter for use on a wellreamer having helical or spiralled cutting parts or teeth.

Another object of the invention is to provide a Well reamerhavingcutters rotatably mounted in a manner so that they may have heavyor deep cutting parts.

Another object of the invention is to provide a simple and effectivemeans for removably or replaceably mounting the rotatable cutters on awell reamer. I

It is another object of the invention to provide a well reamer in whichthe pins carrying the rotatable cutters are not subjected to the wearcaused by rotation of thecutters and therefore do not have to bereplaced with the cutters. 1

Another object of the inventionis to provide a reamer of thecharactergmentionedg in whichreadily replaceable bearings .orbushingsare provided on'the cutter carrying pins to 'rot'atably carry theopposite end portions of the cutters. In accordance with-the presentinvention, the replaceable bushings on the pins within the end portionsof the cutters and the replaceable thrust washers at the ends of thecutters receive all the 'wear caused by th'erotation of the cutters sothat the pins are prevented from becoming worn, and thebushing, in beingprovided in the end portions of the cutters, permit the provision ofheavy or deep cutting teeth on the intermediate or major portions of thecutters.

' A further object of the invention'is to provide a well reamer of thecharacter mentioned involving simple and'eifective means for removablylocking the cutter carrying pins against rotation and longitudinalmovement. Other objects and features of the invention will be best andfully understood from the following detailed description of a typicalform and application of the invention, throughout which description,reference will be had to the accompanying drawing, in which:

Fig. 1 is a side elevation of the reamer pro-- vided by the presentinvention with a portion broken away to illustrate the manner of lockingthe cutter carrying pins against movement. Fig.

2 is a transverse detailed sectional View taken as indicated by line 2-2on Fig. 1. Fig. 3 is an en'- larged fragmentary detailed sectional Viewillustrating one of the cutters and its mounting means, and Figs. 4 and5 are fragmentary transverse detailed sectionalviews taken as indicatedby lines 4% and 55 respectively, on Fig. 3.

The well reamer provided by the present invention includes, generally, abody ll], rotatable cutters l, and means l2 for detachably mounting thecutters H on the body.

The body IU of the reamer is an elongate member adapted to be connectedin a well drilling string. The opposite end portions l3 of the body It!may be cylindrical or round in cross section. Means is provided at theopposite ends of the body In for facilitating its connection inthedrill-' ing string. In the particular embodiment of the inventionillustrated in the drawing, a tapered pin [4 is'provided 'on the upperend of the body l0 and is adapted to be threaded into the socket of adrill collar and a socket I5 is provided in the lower end of the bodyfor receiving the threaded pin of the drilling bit. Itis to beunderstood that if the reamer is to be arranged in the drilling stringabove the drill collar, a socket may be provided in the upper end of thebody H) to receive a pin on a part of the drilling string and a pin maybe provided in the lower end of the body to thread into the socket inthe upper end of the drill collar. Spaced grooves are provided in theupper portion l3 of the body to form annular wickers or ribs forengagement by a fishing tool such as a slip socket, or the like.

The cutter carrying portion ll of the body I0 is of enlarged crosssection and is substantially triangular in cross section as illustratedin Fig. 2 of the drawing. The sides or faces is of the triangular cuttercarrying portion H are preferably flat and vertical as illustrated. Theopposite ends of the triangular portion I! are bevelled to join thecylindrical end parts E3. The apices or corners of the cuttercarryingportion I l are preferably rounded. In accordance with the invention,vertical or longitudinal recesses l9 are provided in the corners of thetriangular body portion ll. The recesses I!) are provided to carry orhold the cutters H and their inner walls are concaved as clearlyillustrated in Fig. 2 of the drawing. The recesses I!) are spaced be-'-tween the opposite ends of the triangular body portion H and their endwalls 2!! are normal to the longitudinal axis of the body.

The cutters II are rotatably mounted in the recesses I 9 by the means l2and their cutting parts project from the open outer ends of the recessesto engage the formation at the wall of the well bore. The cutters II areelongate and of round cross section, and are slightly shorter than therecesses IS. The opposite ends of the cutters l I are flat and normal tothe longitudinal axes of the cutters. Each of the cutters H has acentral longitudinal opening 22 extending completely through it from oneend to the other. The cutters ll rotate on vertical axes and theirperipheral parts act on the formation at the wall of the well bore. Itis a feature of the present invention that the cutters II are providedwith particularly effective cutting parts 24.

The cutting parts 24 extend around the cutters II and are spiralled orhelical. In the form of the invention illustrated in the drawing, thereis a single continuous helical cutting part 24 on each cutter H, itbeing apparent that there may be two or more such parts on each cutter,and that the cutting parts may be broken or interrupted if founddesirable. The cutting parts 24 resemble coarse V-threads, beingsubstantially V-shaped in cross section. In accordance with theinvention, the teeth or cutting parts 24 are comparatively heavy or deepand have sharp cutting edges 25. The lower end portions 26 of thecutters H are frustro-conical and are provided with cutting parts orteeth 21. There is a circumferential series of spaced teeth 21 on eachcutter II. The cutting teeth 21 are comparatively thin or shallow, andin the particular embodiment of the invention illustrated in thedrawing, extend longitudinally of the cutters II. The spiralled orhelical cutting parts 24 are preferably of considerable length and mayextend from the tapered lower portions 21 of the cutters to the upperends of the cutters.

During operation of the reamer the drilling string is rotated in thewell and the cutting parts 24 engage the formation at the side wall ofthe well bore to cut threads in the formation. As the downward movementor feed of the drilling string is comparatively slow, the spiralledcutting parts 24 of the cutters ll shear off the threads as they areformed in the formation and thus enlarge the bore. The threadingengagement of the cutting parts 24 with the formation continuously urgesthe reamer, and parts connected therewith, downwardly and thus providesa downward feed for the drilling tool. The cutters II, in engaging theformation at three circumferentially spaced points, stabilize the lowerend portion of the drilling string and the bit connected therewith andthe threading or feeding action of the spiralled cutting parts 24 actsto further stabilize or steady the reamer and drilling tool.

The means l2 for removably mounting the rotatable cutters II in therecesses [9 includes a removable pin 30 extending longitudinally throughthe opening 22 of each cutter II. The pins 30 project or extend from theopposite ends of the cutters l I and have their lower ends seated insockets 3| in the triangular portion I1 of the body. The upper end parts32 of the pins 30 are enlarged and are carried in longitudinal openings33 extending downwardly from the upper end of the portion l1 to therecesses I9. In accordance with the invention, the pins 30 extendthrough the cutter openings 22 with suitable clearance. The inventionprovides simple and eifective means for holding the cutter carrying pins30 against rotation and longitudinal movement. Horizontal or transverseopenings 34 are provided in the body to intersect the outer edgeportions of the openings 33. Screws 35 extend through the transverseopenings 34 and cooperate with notches 36 in the head portions 32 of thepins to positively hold the pins against rotation and longitudinalmovement. The heads of the screws 35 are threaded into the leading orforward ends of the transverse openings 34 relative to the direction ofrotation of the reamer. The screw heads are countersunk in thetransverse openings 34 and cuttings and mud pack in the openings todependably lock the screws 35 in place.

Renewable or replaceable wear-taking bushings are provided on the pins36 for rotatably carrying the cutters II. A bushing 38 is provided oneach pin 36 to rotatably carry the lower end portion of a cutter II. Thecomparatively shallow teeth 21 of the tapering lower end portions 26 ofthe cutters allow the provision of comparatively deep annular recessesor enlargements 39 in the lower portions of the cutter openings 22 tohold the bushings 33. Due to this relationship between the parts, thebushings 38 may be comparatively large in diameter to presentsubstantial wear receiving surfaces. Reduced lower end portions 40 areprovided on the bushings 39 and are received in sockets 4| at the lowerwalls of the recesses l9. Annular flanges 42 are provided on thebushings 38 and project outwardly between the lower ends of the cuttersII and the lower walls 30 of the recesses 19. The flanges 42 receive thedownward thrusts from the cutters H and effectively space the lower endsof the cutters from the lower walls of the recesses. Novel means areprovided for holding the bushings 38 against rotation. A flat orstraight face 43 is provided on the flange 42 of each bushing tocooperate with a correspondingly shaped face 44 on the body to hold thebushings against turning.

Removable or replaceable bushings 45 are provided on pins 30 forcarrying the upper end portions of the cutters II. The bushings 45 arepressed or otherwise fixed on the pins 30 at the lower ends of the pinenlargements 32. Enlargements 46 are provided in the upper portions ofthe cutter openings 22 to receive or hold the bushings 45. The bushings45 are comparatively long and therefore present substantial wearreceiving surfaces. Thrust washers 41 are provided between the upperends of the cutters II and the upper walls 30 of the recesses l9.Straight or flat faces 48 are provided on the inner sides of the thrustwashers 41 for engaging similar faces 49 on the body to hold the washersagainst turning. The thrust washers 41 surround the enlarged parts 32 ofthe pins 30 as clearly illustrated in Fig. 3 of the drawing.

In assembling a cutter on the body, the assembly of the cutter I l and abushing 38 is positioned in a recess l9 so that the opening 22 of thecutter is in longitudinal alignment with the openings 3| and 33. Inpractice, the end clearance of the cutter with the upper wall of therecess is sufficient to permit the proper arrangement of the end part 40of the bushing in the socket 4 I. The thrust washer 41 may be easilyarranged on the upper end of the cutter with its fiat face against theshoulder 49. The pin 30 may then be passed downwardly through theopening 33 and through the cutter opening 22 and then looked in positionby the screw 35. The bushing 45 is carried by the pin and isproportioned so that it readily passes through the opening 33. Openings50 may be provided in the body to extend from the lower end of theportion '1 to the sockets 3| to permit the pins 3'il'to be loosened anddriven out of position after removal of the screws 35.

The reamer includes means for handling the circulation fluid and forWashing or flushing the cutters I I. A central longitudinal fluidpassage 60 extends through the body I'll from the upper end of the pin Mto the socket I5. Downwardly and outwardly inclined outlet or dischargeopenings 6i extend from the central passage 60 to the inner walls of therecesses I9. The discharge openings GI are preferably substantiallytangential to the rear surfaces of the cutters =I I relative to thedirection of rotation of the reamer. Flow beans or nozzles 62 areprovided in the outer ends of the discharge openings 6 I. The nozzle 62may be threaded into openings '6 I or may be otherwise removablyattached to the body. The openings in the nozzles 62 are considerablysmaller in capacity than the openings 6| so that the velocity of thefluid discharging through them is increased to provide for the eifective flushing of the cutting parts of the cutters II. Further, therestricted openings in the nozzles 62 reduce the quantity of fluiddischarged from the openings GI and cause the nozzles to receive thewear or cutting action due to the discharge of the fluid.

In operation, the drilling string in which the reamer is connected isrotated and the cutting parts 24 and 27 of the cutters II act on theformation at the side walls of the well bore. The spiralled cuttingparts 24 cutcircumferential grooves or threads in. the formation, and asthe downward feed of the reamer is usually comparatively slow, theyshear these threads way from the formation as the tool is rotated. Theengagement of the spiralled cutting parts 24 with the formation acts tourge or feed the reamer and drilling tool downwardly and steadies theaction of the tools. The cutters I I are particularly effective in theircutting action and in being circumferentially spaced, provide for thesmooth operation of the tools. All of the wear caused by rotation of thecutters I I is received by the bushings 38 and 45 and the thrust washer41. As these wear-taking parts are readily replaceable, the tool iseconomical to operate. The cutter carrying pins 30 are not subjected toany wear, and therefore do not have to be replaced together with thecutters or the bushings. The provision of the comparatively shallowcutting parts 27 on the tapered lower ends of the cutters permitscomparatively heavy bushings 38 to be employed to support the lower endsof the cutters. As the bushings 38 and 45 rotatably support the endportions of the cutters, the cutters may be provided with heavy or deepcutting parts 24. The cutters and wear-taking bushings and washers maybe easily and quickly replaced. To remove a cutter I I, the screw 35 isfirst removed and the pin 3!] is then driven out through the opening 33.The upper bushing 45 is removable together with the pin. The cutter I Iand the lower bushing 38 may then be easily lifted out of the recessesI9. In mounting the replacement cutter, the same pin 30 may be employed.The cutter carrying pins 30 are dependably locked in position by thescrews 35 which hold the pins against turning and longitudinal movement.The lock screws 35 are dependably set or retained in posi tion by theaccumulations of mud etc., in the forward ends of the openings 34 whichcover the heads of the screws. The circulation fluid under pressuredischarging from the nozzle 62 effectively flushes the cutting parts ofthe cutters: The reamer provided by the present invention is simple andinexpensive of manufacture and may be readily provided with replacementcutters and wear-taking bushings and washers.

Having described onlya typical form and application, I do not Wish to berestricted or limited to the specific form or application herein setforth, but wish to reserve to myself any modifications or variationsthat may appear to those skilled in the art or fall within the scope ofthe following claims.

Having described my invention, I claim:

1. A well reamer including, a body having a recess, a cutter having alongitudinal opening, and means for rotatably mounting the cutter in therecess, said means including a removable pin extending through therecess and passing through said opening in the cutter, and replaceablebushings on the pin rotatably carrying the opposite end portions of thecutter, the bores of the bushings being of less diameter than saidopening whereby the bushings space the wall of said opening out offrictional contact with the 2. A well reamer including, a body having arecess, a cutter having a longitudinal opening, said opening having anenlarged portion at each of its ends, a removable pin carried by thebody and extending through the cutter opening with clearance, andreplaceable bushings on the pin received by said enlargements of thecutter opening and rotatably carrying the cutter, the bores of thebushings being of less diameter than the cutter opening whereby thebushings prevent frictional contact of the cutter with the pin.

3. A well reamer including, a body having a recess, a cutter having alongitudinal opening, said opening having an enlarged portion at itslower end, and means for rotatably mounting the cutter in the recess,said means including a removable pin carried by the body and freelypassing through the opening in the cutter to be out of contact with thecutter, a replaceable bushing on the pin fitting said enlargement of theopening to rotatably carry the lower portion of the cutter, areplaceable bushing on the pin rotatably carrying the upper portion ofthe cutter, the bores of the bushings being of less diameter than thesaid opening whereby the bushings prevent frictional contact of thecutter with the pin, and. a thrust washer between the upper end of thecutter and the upper wall of the recess.

4. A well reamer including, a body having a recess, a cutter having alongitudinal opening, said opening having an enlarged portion at itslower end, and means for rotatably mounting the cutter in the recess,said means including a removable pin carried by the body and freelypassing through the opening in the cutter without cooperating with itswall, a replaceable bushing on the pin fitting said enlargement of theopening to rotatably carry the lower portion of the cutter, areplaceable bushing on the pin rotat ably carrying the upper portion ofthe cutter, the bushings carrying the cutter so that the wall of thecutter opening is spaced from the pin, and a thrust washer between theupper end of the cutter and the upper wall of the recess. said washerhaving a flat peripheral face cooperating with a corresponding face onthe body whereby it is held against rotation.

5. A well reamer including, a body having a recess, a cutter having alongitudinal opening, said opening having enlarged portions at the upperand lower ends of the cutter, and means for rotatably mounting thecutter in the recess, said means including a removable pin carried bythe body and passing through the opening in the cutter, replaceablebushings fitting said enlargements of the opening and cooperating withthe pin to rotatably carry the upper and lower portions of the cutter,the pin passing bores of the bushings being of less diameter than thesaid opening whereby the bushings hold the wall of said opening out offrictional contact with the pin, and means for holding the bushingsagainst rotation.

6. In a well reamer, a body having an external recess, a cutter having afrusto-conical lower portion, there being a longitudinal opening in thecutter having an enlargement in the lower portion of the cutter, aremovable pin carried by the body andextending through the opening inthe cutter with suitable clearance, a replaceable bushing on the pinreceived in the enlargement of the cutter opening, the bore of thebushing being of less diameter than said opening whereby the bushingprevents frictional contact of the wall of said opening with the pin,and cutting parts on the frusto-conical portion of the cutter, thecutting parts being comparatively shallow whereby said enlargement andbushing may be of large diameter.

'7. A well reamer including a body having an external recess and socketsin the opposite end walls of the recess, a cutter having a longitudinalopening and a socket at the upper end of the opening, a pin passingthrough said opening without contacting its wall and having its lowerend carried in one of the first mentioned sockets, replaceable means onthe pin rotatably supporting the lower end of the cutter, an enlargementon the pin carried in the other of the first mentioned sockets andpresenting a downwardly facing shoulder, and a replaceable bushingcarried in said socket of the cutter engaging the pin to rotatablysupport the upper end of the cutter and bearing upwardly against saidshoulder.

JESSE C. WRIGHT.

